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11210 libm should be cstyle(1ONBLD) clean
@@ -16,13 +16,15 @@
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
+
/*
* Copyright 2011 Nexenta Systems, Inc. All rights reserved.
*/
+
/*
* Copyright 2005 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
@@ -139,24 +141,18 @@
#if defined(__i386) && !defined(__amd64)
extern int __swapRP(int);
#endif
static const int init_jk[] = { 3, 4, 4, 6 }; /* initial value for jk */
-
static const double pio2[] = {
- 1.57079625129699707031e+00,
- 7.54978941586159635335e-08,
- 5.39030252995776476554e-15,
- 3.28200341580791294123e-22,
- 1.27065575308067607349e-29,
- 1.22933308981111328932e-36,
- 2.73370053816464559624e-44,
- 2.16741683877804819444e-51,
+ 1.57079625129699707031e+00, 7.54978941586159635335e-08,
+ 5.39030252995776476554e-15, 3.28200341580791294123e-22,
+ 1.27065575308067607349e-29, 1.22933308981111328932e-36,
+ 2.73370053816464559624e-44, 2.16741683877804819444e-51,
};
-static const double
- zero = 0.0,
+static const double zero = 0.0,
one = 1.0,
half = 0.5,
eight = 8.0,
eighth = 0.125,
two24 = 16777216.0,
@@ -166,10 +162,11 @@
__rem_pio2m(double *x, double *y, int e0, int nx, int prec, const int *ipio2)
{
int jz, jx, jv, jp, jk, carry, n, iq[20];
int i, j, k, m, q0, ih;
double z, fw, f[20], fq[20], q[20];
+
#if defined(__i386) && !defined(__amd64)
int rp;
rp = __swapRP(fp_extended);
#endif
@@ -178,116 +175,134 @@
jp = jk = init_jk[prec];
/* determine jx,jv,q0, note that 3>q0 */
jx = nx - 1;
jv = (e0 - 3) / 24;
+
if (jv < 0)
jv = 0;
+
q0 = e0 - 24 * (jv + 1);
/* set up f[0] to f[jx+jk] where f[jx+jk] = ipio2[jv+jk] */
j = jv - jx;
m = jx + jk;
+
for (i = 0; i <= m; i++, j++)
- f[i] = (j < 0)? zero : (double)ipio2[j];
+ f[i] = (j < 0) ? zero : (double)ipio2[j];
/* compute q[0],q[1],...q[jk] */
for (i = 0; i <= jk; i++) {
for (j = 0, fw = zero; j <= jx; j++)
- fw += x[j] * f[jx+i-j];
+ fw += x[j] * f[jx + i - j];
+
q[i] = fw;
}
jz = jk;
+
recompute:
/* distill q[] into iq[] reversingly */
for (i = 0, j = jz, z = q[jz]; j > 0; i++, j--) {
fw = (double)((int)(twon24 * z));
iq[i] = (int)(z - two24 * fw);
- z = q[j-1] + fw;
+ z = q[j - 1] + fw;
}
/* compute n */
z = scalbn(z, q0); /* actual value of z */
z -= eight * floor(z * eighth); /* trim off integer >= 8 */
n = (int)z;
z -= (double)n;
ih = 0;
+
if (q0 > 0) { /* need iq[jz-1] to determine n */
- i = (iq[jz-1] >> (24 - q0));
+ i = (iq[jz - 1] >> (24 - q0));
n += i;
- iq[jz-1] -= i << (24 - q0);
- ih = iq[jz-1] >> (23 - q0);
+ iq[jz - 1] -= i << (24 - q0);
+ ih = iq[jz - 1] >> (23 - q0);
} else if (q0 == 0) {
- ih = iq[jz-1] >> 23;
+ ih = iq[jz - 1] >> 23;
} else if (z >= half) {
ih = 2;
}
if (ih > 0) { /* q > 0.5 */
n += 1;
carry = 0;
+
for (i = 0; i < jz; i++) { /* compute 1-q */
j = iq[i];
+
if (carry == 0) {
if (j != 0) {
carry = 1;
iq[i] = 0x1000000 - j;
}
} else {
iq[i] = 0xffffff - j;
}
}
+
if (q0 > 0) { /* rare case: chance is 1 in 12 */
switch (q0) {
case 1:
- iq[jz-1] &= 0x7fffff;
+ iq[jz - 1] &= 0x7fffff;
break;
case 2:
- iq[jz-1] &= 0x3fffff;
+ iq[jz - 1] &= 0x3fffff;
break;
}
}
+
if (ih == 2) {
z = one - z;
+
if (carry != 0)
z -= scalbn(one, q0);
}
}
/* check if recomputation is needed */
if (z == zero) {
j = 0;
+
for (i = jz - 1; i >= jk; i--)
j |= iq[i];
+
if (j == 0) { /* need recomputation */
/* set k to no. of terms needed */
- for (k = 1; iq[jk-k] == 0; k++)
+ for (k = 1; iq[jk - k] == 0; k++)
;
/* add q[jz+1] to q[jz+k] */
for (i = jz + 1; i <= jz + k; i++) {
- f[jx+i] = (double)ipio2[jv+i];
+ f[jx + i] = (double)ipio2[jv + i];
+
for (j = 0, fw = zero; j <= jx; j++)
- fw += x[j] * f[jx+i-j];
+ fw += x[j] * f[jx + i - j];
+
q[i] = fw;
}
+
jz += k;
goto recompute;
}
}
/* cut out zero terms */
if (z == zero) {
jz -= 1;
q0 -= 24;
+
while (iq[jz] == 0) {
jz--;
q0 -= 24;
}
} else { /* break z into 24-bit if neccessary */
z = scalbn(z, -q0);
+
if (z >= two24) {
fw = (double)((int)(twon24 * z));
iq[jz] = (int)(z - two24 * fw);
jz += 1;
q0 += 24;
@@ -297,56 +312,68 @@
}
}
/* convert integer "bit" chunk to floating-point value */
fw = scalbn(one, q0);
+
for (i = jz; i >= 0; i--) {
q[i] = fw * (double)iq[i];
fw *= twon24;
}
/* compute pio2[0,...,jp]*q[jz,...,0] */
for (i = jz; i >= 0; i--) {
for (fw = zero, k = 0; k <= jp && k <= jz - i; k++)
- fw += pio2[k] * q[i+k];
- fq[jz-i] = fw;
+ fw += pio2[k] * q[i + k];
+
+ fq[jz - i] = fw;
}
/* compress fq[] into y[] */
switch (prec) {
case 0:
fw = zero;
+
for (i = jz; i >= 0; i--)
fw += fq[i];
- y[0] = (ih == 0)? fw : -fw;
+
+ y[0] = (ih == 0) ? fw : -fw;
break;
case 1:
case 2:
fw = zero;
+
for (i = jz; i >= 0; i--)
fw += fq[i];
- y[0] = (ih == 0)? fw : -fw;
+
+ y[0] = (ih == 0) ? fw : -fw;
fw = fq[0] - fw;
+
for (i = 1; i <= jz; i++)
fw += fq[i];
- y[1] = (ih == 0)? fw : -fw;
+
+ y[1] = (ih == 0) ? fw : -fw;
break;
default:
+
for (i = jz; i > 0; i--) {
- fw = fq[i-1] + fq[i];
- fq[i] += fq[i-1] - fw;
- fq[i-1] = fw;
+ fw = fq[i - 1] + fq[i];
+ fq[i] += fq[i - 1] - fw;
+ fq[i - 1] = fw;
}
+
for (i = jz; i > 1; i--) {
- fw = fq[i-1] + fq[i];
- fq[i] += fq[i-1] - fw;
- fq[i-1] = fw;
+ fw = fq[i - 1] + fq[i];
+ fq[i] += fq[i - 1] - fw;
+ fq[i - 1] = fw;
}
+
for (fw = zero, i = jz; i >= 2; i--)
fw += fq[i];
+
if (ih == 0) {
y[0] = fq[0];
y[1] = fq[1];
y[2] = fw;
} else {